import java.util.Date;

/**
 * @author ：MJS
 * @date ：Created in 2021/6/8  23:27
 * @description：TODO
 */
public class test {

    public static void main(String[] args) {
        System.out.println(f(30));
    }

    private static int f(int x) {
        if(x==1 || x==2){
            return 1;
        }else{
            return f(x-1)+f(x-2);
        }
    }

}
